Third that; unbox it outside or at street level.
Mine went up two flights of extremely tight stairs to my attic studio; the pallet wouldn't even fit through the front door.
Also keep in mind that once it's filled with ink, tipping it is a very, very bad idea. (I have no idea how i'll get it back down the stairs when I change rooms, but I expect it will involve either a hoist or total ink purge.)